Hitherto a conventional controlled atmosphere storage chamber was described in Australian Patent 628067 which included means for generating cooled and pressurised air such as an air conditioner, one or more feed ducts in fluid communication with the air conditioner for circulating the cooled and pressurised air throughout the chamber, a plurality of hollow storage shelves having strip lighting in the form of fluorescent tubes mounted to the underside of each shelf and return ducts for returning heat laden spent air to the air conditioner which are located in the hollow interior of each storage shelf. There was also provided humidifying ducts for circulation of humidified air throughout the chamber.
The storage chamber of Australian Patent 628067 was characterised by the separation of the feed ducts and return ducts in such a manner that the flow of air within the chamber was such as to control heat emission within the vicinity of each lighting strip within a surrounding envelope that represented only a minor proportion of the total volume of the chamber.
The controlled storage chamber of Australian Patent 628067 was generally constructed as an experimental prototype and during operation it was found to be unsatisfactory in several respects because there was no proper control placed on suitable monitoring of variables which contributed to a controlled atmosphere such as (i) heat, (ii) air pressure, (iii) air velocity, and (iv) humidity. Without such monitoring taking place it was found in practice that "hot spots" or localised heat pockets occurred in the chamber which was extremely deleterious to perishable products placed on the storage shelves leading to product spoilage, lack of germination of plants, lack of proper maintenance of cell cultures and bacterial cultures and introduction of pathogens into a sterile atmosphere.
This therefore meant that the controlled atmosphere storage room of Australian Patent 628067 was neither energy efficient nor cost efficient and did not provide a precisely monitored atmosphere in respect of the abovementioned variables which is essential for properly conducted research facilities especially in biological applications involving recombinant DNA technology or tissue culture experiments.
It therefore is an object of the invention to provide a controlled atmosphere storage chamber which may alleviate the abovementioned disadvantages of the prior art.